A hybrid seismic fragility model for territorial-scale seismic vulnerability assessment of masonry buildings is developed and presented in this paper. The method combines expert-judgment and mechanical approaches to derive typological fragility curves for Italian residential masonry building stock. The first classifies Italian masonry buildings in five different typological classes as function of age of construction, structural typology, and seismic behaviour and damaging of buildings observed following the most severe earthquakes occurred in Italy. The second, based on numerical analyses results conducted on building prototypes, provides all the parameters necessary for developing fragility functions. Peak-Ground Acceleration (PGA) at Ultimate Limit State attainable by each building’s class has been chosen as an Intensity Measure to represent fragility curves: three types of curve have been developed, each referred to mean, maximum and minimum value of PGAs defined for each building class. To represent the expected damage scenario for increasing earthquake intensities, a correlation between PGAs and Mercalli-Cancani-Sieber macroseismic intensity scale has been used and the corresponding fragility curves developed. Results show that the proposed building’s classes are representative of the Italian masonry building stock and that fragility curves are effective for predicting both seismic vulnerability and expected damage scenarios for seismic-prone areas. Finally, the fragility curves have been compared with empirical curves obtained through a macroseismic approach on Italian masonry buildings available in literature, underlining the differences between the methods.

本文开发并介绍了用于砖石建筑地域尺度地震脆弱性评估的混合地震易损性模型。该方法结合了专家判断和机械方法来推导出意大利住宅砌体建筑存量的类型脆弱性曲线。第一个将意大利砌体建筑分为五个不同的类型分类，根据建筑年龄、结构类型、地震行为和在意大利发生的最严重地震后观察到的建筑物损坏情况。第二个基于对构建原型进行的数值分析结果，提供了开发脆弱性函数所需的所有参数。峰地加速度 ( PGA)) 在极限状态下每个建筑物等级可达到的状态已被选择作为强度度量来表示脆性曲线：已经开发了三种类型的曲线，每种类型都指为每个建筑物等级定义的PGA的平均值、最大值和最小值。为了表示地震强度增加的预期破坏情况，PGA之间的相关性s 和 Mercalli-Cancani-Sieber 宏观地震强度标度已被使用，并开发了相应的脆性曲线。结果表明，拟建建筑的等级代表了意大利砖石建筑存量，而且脆性曲线可有效预测地震易发地区的地震脆弱性和预期损坏情况。最后，将脆性曲线与通过文献中可用的意大利砖石建筑的宏观地震方法获得的经验曲线进行了比较，强调了这些方法之间的差异。